The short answer
- ARW is a proprietary TIFF-based raster image format that stores raw sensor data from certain Sony cameras, and support can depend on the camera model and software version.
- Open an ARW file in Sony Imaging Edge Desktop to view, edit, and process its RAW data. On Windows, install a current supported release, open the file from the application, and export a rendered copy if another program needs JPEG or TIFF. If a third-party program cannot open the file, update it and check whether it supports the exact Sony camera model; Sony notes that profiles for new cameras may not yet be present in Adobe software and does not guarantee third-party compatibility.
- ARW is documented as a TIFF-based raster image and metadata container, with no recorded script, macro, or other active-execution mechanism. This makes active-content risk low, but not zero: untrusted files still pass through complex RAW/TIFF parsers. Use supported, updated software and do not treat a familiar extension or a successful preview as proof that a file is trustworthy.
ARW File: How to Open and Convert Sony Alpha Raw Images
Sony developed ARW for raw images produced by certain cameras. PRONOM records ARW 1.x as fmt/191 and ARW 2.x as fmt/1127; both use the .arw extension. A particular camera may produce a specific version and bit depth: Sony lists ARW 2.3 with 14-bit RAW output for the ILCE-7.
Use Imaging Edge Desktop to process ARW and save the result as JPEG or TIFF. JPEG is lossy and discards the adjustable raw sensor representation. TIFF avoids JPEG's lossy encoding, but rendering still fixes choices such as white balance, color interpretation, gamma, noise reduction, and sharpening; a TIFF therefore is not equivalent to the original ARW.
How to open it
Open an ARW file in Sony Imaging Edge Desktop to view, edit, and process its RAW data. On Windows, install a current supported release, open the file from the application, and export a rendered copy if another program needs JPEG or TIFF. If a third-party program cannot open the file, update it and check whether it supports the exact Sony camera model; Sony notes that profiles for new cameras may not yet be present in Adobe software and does not guarantee third-party compatibility.
Open an ARW file in Sony Imaging Edge Desktop to view, edit, and process its RAW data. On Windows, install a current supported release, open the file from the application, and export a rendered copy if another program needs JPEG or TIFF. If a third-party program cannot open the file, update it and check whether it supports the exact Sony camera model; Sony notes that profiles for new cameras may not yet be present in Adobe software and does not guarantee third-party compatibility.
Use Imaging Edge Desktop to process ARW and save the result as JPEG or TIFF. JPEG is lossy and discards the adjustable raw sensor representation. TIFF avoids JPEG's lossy encoding, but rendering still fixes choices such as white balance, color interpretation, gamma, noise reduction, and sharpening; a TIFF therefore is not equivalent to the original ARW.
File safety
ARW is documented as a TIFF-based raster image and metadata container, with no recorded script, macro, or other active-execution mechanism. This makes active-content risk low, but not zero: untrusted files still pass through complex RAW/TIFF parsers. Use supported, updated software and do not treat a familiar extension or a successful preview as proof that a file is trustworthy.
An unknown sender, a name ending in two extensions, or contents that do not match the extension — check before you open it.
Converting it
Use Imaging Edge Desktop to process ARW and save the result as JPEG or TIFF. JPEG is lossy and discards the adjustable raw sensor representation. TIFF avoids JPEG's lossy encoding, but rendering still fixes choices such as white balance, color interpretation, gamma, noise reduction, and sharpening; a TIFF therefore is not equivalent to the original ARW.
Convert a copy, never the original, then compare quality, metadata, and layout against what you started with.
Common questions
What is a Sony ARW file used for?
An ARW file stores raw image data and metadata from certain Sony cameras in a proprietary TIFF-based raster format. It is intended for RAW processing before a conventional image is produced.
How do I open an ARW file in Sony Imaging Edge Desktop?
Install a current supported version of Imaging Edge Desktop, open the ARW from the application, and use its RAW viewing and processing features. You can then save a rendered result as JPEG or TIFF.
How do I open a Sony ARW file on Windows?
Use Sony Imaging Edge Desktop on Windows. If another Windows application rejects the file, update that application and verify support for the exact camera model, because ARW compatibility can vary by model and software version.
Why will an ARW file from a new Sony camera not open?
The installed software may not yet include a RAW profile for that camera model. Update the RAW application and check its model support; if third-party support is unavailable, use Sony Imaging Edge Desktop.
Should I use ARW 1.x or ARW 2.x?
You normally use the version produced by the camera rather than choosing one manually. PRONOM registers ARW 1.x and 2.x separately, while both use .arw, so software must recognize the file content and camera output.
How can I convert a Sony ARW file to JPEG?
Process the ARW in Imaging Edge Desktop and save the result as JPEG. The conversion renders the raw sensor data and uses lossy JPEG encoding, so keep the original ARW if you may want different processing later.
Is an ARW file from an unknown source safe to open?
ARW has no documented active script or macro mechanism, so its active-content risk is low. It still must be parsed by RAW/TIFF software, so open untrusted files only with supported, updated software.
Is an ARW file just a TIFF file with another extension?
No. ARW is TIFF-based, but it is a proprietary Sony RAW format with Sony markers and camera data. A rendered TIFF fixes processing choices and is not equivalent to the original ARW.
Can an ARW file be identified reliably from the .arw extension alone?
No. PRONOM identification starts with the little-endian TIFF header and also checks later SONY and MakerNote FileFormat data to distinguish ARW versions. An extension alone is insufficient.
Does a successful ARW preview prove that the image data is trustworthy?
No. A preview only shows that the software parsed enough data to display an image. It does not establish the file's origin, integrity, or truthfulness.
Related formats
Sources
PRONOM: Sony ARW RAW Image File 1.x (fmt/191) · The National Archives (UK), PRONOM
PRONOM: Sony ARW RAW Image File 2.x and identification signature · The National Archives (UK), PRONOM
ILCE-7 Specifications · Sony official support
Can't open, view, or edit RAW images on my computer · Sony official support
Camera Raw Formats (Group Description) · Library of Congress, Sustainability of Digital Formats